James weir graydon



UNITED STATES PATENT OFFICE.

JAMES wEIR GRAYDoN, or WASHINGTON, DISTRICT oE ooLUMBIRASSIeNoR To ROBERT soUTHwoRTH LAWRENCE, ori LoNDoN,ENeLA-ND,

ELECTRIC-AL FUSE FO R lOl-RDN/ltNCE-S H ELLS.

SPIE'.CIIFICA'IIOII' forming part of Letters Patent No.' 399,879, dated March. 19, 1889.

Application nea october 9,1888. Seriana. 287,631. (Nomad.)

`To all whom t may concer-n.-

Be it known that I, JAMES WEIR GRAYDON,

siding at Washington, in the District of Columbia, have invented certain new and useful Improvementsin Electrical Fuses for Ordnance-Shells, of which the following is a speciication, reference being had therein to the accompanying drawings.

My invention relates to an electrical fuse for ordnance-shells; and it has for its object to provide a fuse which will be ignited by electricity when the shell strikes.

The invention will first be described in connection with the-accompanying drawing, and

then pointed out in -the claims.

The drawing is a longitudinal section of a lshell provided with my improved electrical away.

. A represents the shell closed at the rear end by a screw-plug, B.

` C are the battery-cups, which are held in place by a boxing, D, resting against the inner end of plug B, which boxing, in turn, is held in place by the bursting-charge to be placed in the charge-chamber E of the shell. F represents. the fuse-tube, of any suitable rigid material, extending from near the front end to near the rear end of the charge-chamber and perforated throughout its length. '[herearend of this tube passes through a perforation in boxing D, and is held a short distance from the plug B byaange,f,wl1ich rests against the front end of the boxing, while. the forward end of the tube passes through an opening in a disk, d, at the front end of the charge-chamber. The tube is filled with any suitable fuse material-as fulminate of mercury m--inclosed in thin parained paper o, and to its lower end lis secured a plati' num disk, G, with which are connected wires 'n p from opposite poles of the battery.

N and P are wires connected to the negative and positive poles of the battery and leading to the front end of the charge-chamber,

where they are secured to binding-posts 1 1,

inserted in a hollow sci'ew-plug, 2, screwed into the shell, the said posts being provided with the usual contact-plates 3 3.

. H represents a metal plunger which passes through a-perforation, 4, in the forward end 'of the shell andthrough the hollow' plug 2, it

being held normally out of contact with the contact-plates by means of a coiled spring, s, seated in a recess, 5, formed in the front end of the shell and surrounding the plunger, the

- lower end of said spring bearing on the bottom of the recess and its upper end engaging with a flange, h, on thel plunger, a pin, -t, passed through the inner end of the plunger, limiting its outward movement.

In order to prevent the plunger being accidentally pushed into cont-act .wi th the contactplates, and also to prevent moisture entering the shell, I cover the outer end of the plunger with a soft-metal cap -or shield, S, which is Screw-threaded internally to Screw onto a screw-threaded projection, T, on the front end of the shell.

The operation of my electrical fuse is very simple. be broken and the plunger forced into contact with the contact-plates, thus closing the electric circuit, when the platinum disk will at once become suicientlyheated to ignite the` fusematerial, the -force of whose explosion will be transmitted to all-parts of the bursting-charge through the perforations in the tube; and if the bursting-charge is dynamite or other high explosive the detonation will be simultaneous and complete. y

Having thus described my invention, what Iclaim as new, and desire to Secure by Letters Patent, is-

lQAn electrical fuse for shells, consisting of a battery, a perforated fuse-tube containing the fuse material, said tube provided with a platinum disk and extending longitudinally of t-he charge-chamber in the shell, batterywires norma y out of circuit, and a movable As the shell Strikes, the shield S will plunger `in one of the walls ofthe shell, adapted to he forced longitudinally between of a battery located at the rear end of the f charge-chamber of the shell, a perforated fuse-tube containing the fuse material, said tube provided at its rear end with a platinum disk and extending longitudinally of the charge-ehamber, binding-posts provided with contact-plates at the front endvof the chargechambel', battery-wires normally out of -circuit leading to and connected with said binding-posts, and a movable plunger in the front wall of the shell, adapted to be forced longitudinally between said contact-plates to close zo the electric circuit, all'combined substantially asset forth. y e

In testimony whereof I affix my signature in presence of two witnesses.

JAMES WEIR GRAYDON. Witnesses:

WM. HUNTER MYERS, CHARLES F. ROBERTS. 

